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-rw-r--r--fs/namespace.c120
1 files changed, 56 insertions, 64 deletions
diff --git a/fs/namespace.c b/fs/namespace.c
index d28d30b13043..85b5f7bea82e 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1643,13 +1643,18 @@ static inline bool may_mount(void)
return ns_capable(current->nsproxy->mnt_ns->user_ns, CAP_SYS_ADMIN);
}
+#ifdef CONFIG_MANDATORY_FILE_LOCKING
static inline bool may_mandlock(void)
{
-#ifndef CONFIG_MANDATORY_FILE_LOCKING
- return false;
-#endif
return capable(CAP_SYS_ADMIN);
}
+#else
+static inline bool may_mandlock(void)
+{
+ pr_warn("VFS: \"mand\" mount option not supported");
+ return false;
+}
+#endif
/*
* Now umount can handle mount points as well as block devices.
@@ -1675,8 +1680,6 @@ int ksys_umount(char __user *name, int flags)
if (!(flags & UMOUNT_NOFOLLOW))
lookup_flags |= LOOKUP_FOLLOW;
- lookup_flags |= LOOKUP_NO_EVAL;
-
retval = user_path_mountpoint_at(AT_FDCWD, name, lookup_flags, &path);
if (retval)
goto out;
@@ -1725,7 +1728,7 @@ static bool is_mnt_ns_file(struct dentry *dentry)
dentry->d_fsdata == &mntns_operations;
}
-struct mnt_namespace *to_mnt_ns(struct ns_common *ns)
+static struct mnt_namespace *to_mnt_ns(struct ns_common *ns)
{
return container_of(ns, struct mnt_namespace, ns);
}
@@ -2353,7 +2356,7 @@ static struct file *open_detached_copy(struct path *path, bool recursive)
return file;
}
-SYSCALL_DEFINE3(open_tree, int, dfd, const char *, filename, unsigned, flags)
+SYSCALL_DEFINE3(open_tree, int, dfd, const char __user *, filename, unsigned, flags)
{
struct file *file;
struct path path;
@@ -2463,6 +2466,28 @@ static void set_mount_attributes(struct mount *mnt, unsigned int mnt_flags)
unlock_mount_hash();
}
+static void mnt_warn_timestamp_expiry(struct path *mountpoint, struct vfsmount *mnt)
+{
+ struct super_block *sb = mnt->mnt_sb;
+
+ if (!__mnt_is_readonly(mnt) &&
+ (ktime_get_real_seconds() + TIME_UPTIME_SEC_MAX > sb->s_time_max)) {
+ char *buf = (char *)__get_free_page(GFP_KERNEL);
+ char *mntpath = buf ? d_path(mountpoint, buf, PAGE_SIZE) : ERR_PTR(-ENOMEM);
+ struct tm tm;
+
+ time64_to_tm(sb->s_time_max, 0, &tm);
+
+ pr_warn("%s filesystem being %s at %s supports timestamps until %04ld (0x%llx)\n",
+ sb->s_type->name,
+ is_mounted(mnt) ? "remounted" : "mounted",
+ mntpath,
+ tm.tm_year+1900, (unsigned long long)sb->s_time_max);
+
+ free_page((unsigned long)buf);
+ }
+}
+
/*
* Handle reconfiguration of the mountpoint only without alteration of the
* superblock it refers to. This is triggered by specifying MS_REMOUNT|MS_BIND
@@ -2488,6 +2513,9 @@ static int do_reconfigure_mnt(struct path *path, unsigned int mnt_flags)
if (ret == 0)
set_mount_attributes(mnt, mnt_flags);
up_write(&sb->s_umount);
+
+ mnt_warn_timestamp_expiry(path, &mnt->mnt);
+
return ret;
}
@@ -2528,6 +2556,9 @@ static int do_remount(struct path *path, int ms_flags, int sb_flags,
}
up_write(&sb->s_umount);
}
+
+ mnt_warn_timestamp_expiry(path, &mnt->mnt);
+
put_fs_context(fc);
return err;
}
@@ -2735,6 +2766,8 @@ static int do_new_mount_fc(struct fs_context *fc, struct path *mountpoint,
if (IS_ERR(mnt))
return PTR_ERR(mnt);
+ mnt_warn_timestamp_expiry(mountpoint, mnt);
+
error = do_add_mount(real_mount(mnt), mountpoint, mnt_flags);
if (error < 0)
mntput(mnt);
@@ -2768,8 +2801,6 @@ static int do_new_mount(struct path *path, const char *fstype, int sb_flags,
put_filesystem(type);
return -EINVAL;
}
- } else {
- subtype = "";
}
}
@@ -2948,39 +2979,10 @@ static void shrink_submounts(struct mount *mnt)
}
}
-/*
- * Some copy_from_user() implementations do not return the exact number of
- * bytes remaining to copy on a fault. But copy_mount_options() requires that.
- * Note that this function differs from copy_from_user() in that it will oops
- * on bad values of `to', rather than returning a short copy.
- */
-static long exact_copy_from_user(void *to, const void __user * from,
- unsigned long n)
-{
- char *t = to;
- const char __user *f = from;
- char c;
-
- if (!access_ok(from, n))
- return n;
-
- while (n) {
- if (__get_user(c, f)) {
- memset(t, 0, n);
- break;
- }
- *t++ = c;
- f++;
- n--;
- }
- return n;
-}
-
void *copy_mount_options(const void __user * data)
{
- int i;
- unsigned long size;
char *copy;
+ unsigned size;
if (!data)
return NULL;
@@ -2989,22 +2991,16 @@ void *copy_mount_options(const void __user * data)
if (!copy)
return ERR_PTR(-ENOMEM);
- /* We only care that *some* data at the address the user
- * gave us is valid. Just in case, we'll zero
- * the remainder of the page.
- */
- /* copy_from_user cannot cross TASK_SIZE ! */
- size = TASK_SIZE - (unsigned long)data;
- if (size > PAGE_SIZE)
- size = PAGE_SIZE;
+ size = PAGE_SIZE - offset_in_page(data);
- i = size - exact_copy_from_user(copy, data, size);
- if (!i) {
+ if (copy_from_user(copy, data, size)) {
kfree(copy);
return ERR_PTR(-EFAULT);
}
- if (i != PAGE_SIZE)
- memset(copy + i, 0, PAGE_SIZE - i);
+ if (size != PAGE_SIZE) {
+ if (copy_from_user(copy + size, data + size, PAGE_SIZE - size))
+ memset(copy + size, 0, PAGE_SIZE - size);
+ }
return copy;
}
@@ -3046,7 +3042,7 @@ long do_mount(const char *dev_name, const char __user *dir_name,
return -EINVAL;
/* ... and get the mountpoint */
- retval = user_path(dir_name, &path);
+ retval = user_path_at(AT_FDCWD, dir_name, LOOKUP_FOLLOW, &path);
if (retval)
return retval;
@@ -3294,8 +3290,8 @@ struct dentry *mount_subtree(struct vfsmount *m, const char *name)
}
EXPORT_SYMBOL(mount_subtree);
-int ksys_mount(const char __user *dev_name, const char __user *dir_name,
- const char __user *type, unsigned long flags, void __user *data)
+SYSCALL_DEFINE5(mount, char __user *, dev_name, char __user *, dir_name,
+ char __user *, type, unsigned long, flags, void __user *, data)
{
int ret;
char *kernel_type;
@@ -3328,12 +3324,6 @@ out_type:
return ret;
}
-SYSCALL_DEFINE5(mount, char __user *, dev_name, char __user *, dir_name,
- char __user *, type, unsigned long, flags, void __user *, data)
-{
- return ksys_mount(dev_name, dir_name, type, flags, data);
-}
-
/*
* Create a kernel mount representation for a new, prepared superblock
* (specified by fs_fd) and attach to an open_tree-like file descriptor.
@@ -3483,8 +3473,8 @@ err_fsfd:
* Note the flags value is a combination of MOVE_MOUNT_* flags.
*/
SYSCALL_DEFINE5(move_mount,
- int, from_dfd, const char *, from_pathname,
- int, to_dfd, const char *, to_pathname,
+ int, from_dfd, const char __user *, from_pathname,
+ int, to_dfd, const char __user *, to_pathname,
unsigned int, flags)
{
struct path from_path, to_path;
@@ -3593,11 +3583,13 @@ SYSCALL_DEFINE2(pivot_root, const char __user *, new_root,
if (!may_mount())
return -EPERM;
- error = user_path_dir(new_root, &new);
+ error = user_path_at(AT_FDCWD, new_root,
+ LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &new);
if (error)
goto out0;
- error = user_path_dir(put_old, &old);
+ error = user_path_at(AT_FDCWD, put_old,
+ LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &old);
if (error)
goto out1;
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